This assembly is from 1957 from a Raytheon manual, but can be modernized using a BC548, 6 V power supply and common 100 mA relays.
The circuit is from National Semiconductor's Linear Applications Handbook. The operational...
This circuit is old, causing LEDs to be lit sequentially. Several types of games can be programmed using...
This circuit of the 70's uses transistors of the time. The circuit can amplify signals from 10 Hz...